1. Field of the Invention
The invention relates to abrasive articles.
2. Discussion of the Art
Abrasive articles typically comprise a plurality of abrasive particles and a binder. There are a number of different types of abrasive articles on the market. These include (1) coated abrasive articles, in which the binder bonds the abrasive particles to a backing material (e.g., "sandpaper"), (2) lapping coated abrasive articles, in which the abrasive particles are first dispersed in a binder precursor and the resulting dispersion is bonded to a backing material, (3) bonded abrasive articles, in which the binder bonds the abrasive particles together to form a shaped mass, e.g., a grinding wheel, and (4) nonwoven abrasive articles, in which the binder bonds the abrasive particles into a nonwoven fibrous substrate.
The binder of the abrasive article is typically formed by curing a binder precursor, which is in liquid form. The binder precursor typically comprises a resin. During the manufacture of the abrasive article, the binder precursor is exposed to an energy source, which results in the polymerization of the resin, thereby forming the binder. The energy source can provide thermal energy, or radiation energy, e.g., electron beam, ultraviolet light, or visible light. In recent years, radiation-curable resins have been employed because of their advantages over thermally-curable resins, e.g., faster cure times, lower capital investments in buildings and equipment, and lower energy costs. Examples of radiation-curable resins are acrylate-based resins.
The high viscosity of many radiation-curable resins tends to cause processing problems. Accordingly, organic solvents or diluents are sometimes added to lower the viscosity of binder precursors that comprise radiation-curable resins. However, removal and recovery of organic solvents is expensive, and solvents and diluents pose safety and environmental concerns.
Radiation-curable resins have been combined with thermally-curable resins, e.g., phenolics, to improve the properties of the binder.